If a and b are positive, is (a^-1 + b^-1)^-1 less than (a^-1b^-1)^-1?
(1) a = 2b
(2) a + b > 1
Hi, [spoiler]I am getting cnfused since a b could be non-integer... can anyone help? [/spoiler]
DS 2
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The first term - (a^-1 + b^-1)^-1
for any positive value of a and b the first term will always be positive.
coz a^-1 & b^-1 will always be negative so as their addition and then ^-1 of that number will always result in the positive value.
The second term - (a^-1b^-1)^-1
for any positive value of a and b the first term will always be negative.
coz a^-1 & b^-1 will always be negative and their multiplication will always be positive, now ^-1 of the positive number will be again a negative.
So Ans shud be D.
let me know.
for any positive value of a and b the first term will always be positive.
coz a^-1 & b^-1 will always be negative so as their addition and then ^-1 of that number will always result in the positive value.
The second term - (a^-1b^-1)^-1
for any positive value of a and b the first term will always be negative.
coz a^-1 & b^-1 will always be negative and their multiplication will always be positive, now ^-1 of the positive number will be again a negative.
So Ans shud be D.
let me know.
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The ans should be C
The lowest values for which a = 2b and a + b > 0 are
b = 0.4 and a = 0.8.
if u put these values or any values greter than then in all cases u will find ab/a+b is less than ab
pls confirm
The lowest values for which a = 2b and a + b > 0 are
b = 0.4 and a = 0.8.
if u put these values or any values greter than then in all cases u will find ab/a+b is less than ab
pls confirm
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The ans is A
When we simplify the inequality it comes out to be
Is ab/(a+b)<a/b?
now statement 1 is sufficient to answer this question...
OA please
When we simplify the inequality it comes out to be
Is ab/(a+b)<a/b?
now statement 1 is sufficient to answer this question...
OA please
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